Fluid couplings

ABSTRACT

A fluid coupling comprising releasably interconnectable male and female coupling members for interconnecting fluid flow lines. The male coupling member has an inlet and an outlet connectable to a fluid flow line, whilst the female coupling member has an inlet for receiving the inlet of the male coupling member, and an outlet connectable to another fluid flow line. A locking mechanism exerts a retaining influence on the male coupling member, when received within the female coupling member, to connect the coupling members together. A lock release mechanism is operable to remove the retaining influence of the locking mechanism and release the coupling members. The lock release mechanism has a release member manually movable to operate the lock release mechanism. Release member movement includes a preliminary movement to a preparatory position in which the lock release member is then able to operate the lock release mechanism to remove the retaining influence thereof followed by a further movement in at least a non-axial direction which operates the lock release mechanism to remove the retaining influence. Biasing means acts on the release member to bias the release member away from the preparatory position.

This invention relates generally to fluid couplings and in particular tocouplings which incorporate quick connection and release mechanismsbetween male and female coupling members interconnecting fluid flowlines.

A number of fluid couplings of the above type have been developed.Applicant's Australian Patent No. 646972 describes several prior artfluid couplings and an improvement over these. That disclosureparticularly relates to quick connection and release fluid couplings andan improvement over these. That disclosure particularly relates to quickconnection and release fluid couplings in which a male coupling memberis releasably connected to a female coupling member upon insertion ofthe male member into the female member. A locking mechanism acts torelatively lock the male and female members and generally includeslocking elements such as balls suitable to engage in aligned grooves orrecesses in the male and female members. Locking release means are alsoprovided to release the locking elements from the respective grooves orrecesses and thus allow disconnection of the male member from the femalemember.

One feature of these previous fluid couplings is that the lockingrelease means are relatively easy and quick to operate and ideallyrequire only a single unassisted movement action to effect disconnectionrelease. While in many domestic and industrial applications, this isparticularly desirable, it has been found that these types of fluidcouplings may, on occasions, be subject to accidental release by virtueof the release mechanisms employed. While accidental release may occurrelatively infrequently and thus be tolerable for the majority of uses,in situations where accidental release cannot be tolerated, ie. insituations where safety may be jeopardized, in high pressure or highflow fluid hoses, or with volatile or expensive fluids, a more reliablerelease mechanism is preferred, in order that the fluid coupling isdeliberately or positively released only when required.

One such pipe coupling is disclosed in Australian Patent No. 579370. Inthat coupling a cylindrical male member is provided with a grooveextending completely about the circumference of its outer surface, and acylindrical female member is provided with a pair of oppositely locatedchordal apertures. The apertures and groove are relatively so located sothat, when the male and female members are conjoined, a pin driven intoeach aperture engages tangentially in a portion of the groove in themale member, thus locking the two members together. The pins are of aslightly larger diameter than that of the apertures to ensure aninterference fit so that the pins remain fixed in place.

While a fluid coupling conforming to the above parameters serves toensure that accidental release of the coupling is prevented, theconnection arrangement suffers several disadvantages. In particular, theapertures and groove can be difficult to align whilst the pins can beawkward to insert, especially in dirty couplings or blocked apertures.Being separate from the coupling members, the pins can be readily lostor misplaced. Separate tools are required for both the insertion andremoval of the pins, and often considerable mechanical force is requiredto remove the pins and thus effect desired release of the male memberfrom the female member. In addition, unless the pins are fully driveninto the apertures they can tend to snag on objects and fixtures insituations where the flow lines and couplings are being dragged or movedabout. Thus, such a connection arrangement is at least inconvenient andparticularly not suited where release of the coupling may be required ona somewhat regular or frequent basis, or in inconvenient locations.

It is an object of the present invention to overcome or at leastalleviate some or all of the disadvantages of the prior art.

Another object of the present invention is the provision of an improvedfemale coupling member for a fluid coupling.

It is a further and particular object of the invention to provide afluid coupling having interconnectable male and female coupling members,and which generally avoids accidental or unintentional release of themale member relative to the female member.

With these objects in mind, the present invention provides in one aspecta female coupling member, releasably interconnectable with a malecoupling member to form a fluid coupling, the female coupling memberincluding:

a tubular coupling body having an inlet end for axially receiving theinlet end of the male coupling member, and an outlet end connectable toa fluid flow line;

a locking mechanism operable to exert a retaining influence on the malecoupling member, when received within the female coupling member, toreleasably interconnect the male and female coupling members; and,

a lock release mechanism selectively operable to remove the retaininginfluence of the locking mechanism so as to release the male and femalecoupling members, the lock release mechanism including a release memberbeing manually movable to operate the lock release mechanism, movementof the release member including a preliminary movement to a preparatoryposition in which the lock release member is then able to operate thelock release mechanism to remove the retaining influence thereoffollowed by a further movement in at least a non-axial direction whichoperates the lock release mechanism to remove the retaining influence.

In another aspect, the present invention provides a fluid coupling forinterconnecting fluid flow lines, including:

a tubular male coupling member having an inlet end, and an outlet endconnectable to a fluid flow line;

a tubular female coupling member having an inlet end for axiallyreceiving the inlet end of the male coupling member, and an outlet endconnectable to a fluid flow line;

a locking mechanism operable to exert a retaining influence on the malecoupling member, when received within the female coupling member, toreleasably interconnect the male and female coupling members; and,

a lock release mechanism selectively operable to remove the retaininginfluence of the locking mechanism so as to release the male and femalecoupling members, the lock release mechanism including a release memberbeing manually movable at least in a non-axial direction to operate thelock release mechanism, movement of the release member including apreliminary movement to a preparatory position in which the lock releasemember is then able to operate the lock release mechanism to remove theretaining influence thereof followed by a further movement in at least anon-axial direction which operates the lock release mechanism to removethe retaining influence.

This coupling arrangement differs significantly from prior so-called"quick-release" fluid couplings discussed above, which generally includea sleeve member movable in an axial or longitudinal direction withrespect to the axis of he coupling, to a position in which the lockinginfluence of the locking mechanism is removed. The release of suchquick-release fluid couplings may, on occasions be accidentallytriggered by knocking, jolting, or engaging the sleeve member againstanother surface, which serves to induce sufficient axial movement forrelease of the locking mechanism to be effected. That is avoided withthe present invention by provision of the lock release mechanism inwhich a release member is required to undergo non-axial movement.

Preferably, the preliminary movement of the release member is in adirection along a longitudinal axis of the coupling, while the furthermovement is in a direction about the longitudinal axis. In particular,the release member preferably moves in an axial linear direction duringthe preliminary movement, and in compound rotational and linealdirections respectively about and along a longitudinal axis of thecoupling during the further movement.

In one embodiment, the lock release mechanism is carried on the femalecoupling member. The mechanism is slidably carried for sliding duringthe preliminary movement. Moreover, there is at least one screw threadon the female coupling member and at least one co-operable screw threadon the release member. These screw threads progressively interengageupon rotation of the release member to cause the release member to movein the compound rotational and lineal directions during the furthermovement, in this embodiment. In one embodiment, the female couplingmember the female coupling member includes a tubular coupling bodydefining an axial fluid flow passage and the screw thread of the femalecoupling member is provided on an inner surface in the flow passage ofthe coupling body. The release member includes an inner sleeve portionextending into the flow passage and the screw thread of the releasemember is provided on an outer surface of the inner sleeve portion inthis embodiment.

Preferably, the screw threads are disengageable upon reverse directionrotation of the release member. Upon disengagement the screw threads arepreferably axially spaced apart, with the release member being axiallymovable relative to the female coupling member during the preliminarymovement in order to bring the screw threads into engagement.

In one embodiment, the lock release mechanism includes a biasing elementacting on the release member to bias the release member in an axialdirection in which the disengaged screw threads are maintained in spacedapart relation. The release member is then manually movable against thebias to bring the screw threads into engagement. The biasing element isa biasing spring in one embodiment. It is mounted in a circumferentialclearance space formed between the release member and the tubularcoupling body at the inlet end of the female coupling member, and actsbetween the release member and tubular coupling body, in thisembodiment. Multi-start screw threads are provided on the femalecoupling member and the release member in one embodiment.

Preferably, the release member includes an outer sleeve portioncoaxially surrounding the female coupling member and connected to theinner sleeve portion. That outer sleeve portion is manually grippablefor movement to progressively interengage the screw threads. Preferably,the release member also includes a flange portion extending radiallyfrom the inner sleeve portion. The outer sleeve portion is connected tothe flange portion in order to move the inner sleeve portion forengagement of the screw threads.

In one embodiment, the outer sleeve portion and flange portion areformed integral with one another. In another embodiment, the flangeportion has a circumferentially extending and radially outwardly facinggroove. Moreover, the outer sleeve portion has a circumferentiallyextending and inwardly facing flange which engages in the groove toconnect the outer sleeve portion to the flange portion.

In one embodiment, the outer sleeve portion overlies and covers theclearance space and biasing spring between the release member and thetubular coupling body.

The locking mechanism preferably includes a plurality of lockingelements. Those elements are carried by one of the coupling members andmovable between a release position disengaging from the other couplingmember, and a locking position in which the locking members extendbetween the coupling members and engage the other coupling member toreleasably interconnect the coupling members together. The releasemember, upon movement to operate the lock release mechanism, preferablyengages the locking elements and moves them to their release position todisengage the coupling members.

Preferably, the locking mechanism includes a circumferential retainingrecess provided in the female coupling member. The locking elementspreferably include arcuate locking segments positioned in side-by-siderelation along the recess for inward movement from the release positionto the locking position. Preferably, the locking elements are generallyradially movable between the release and locking positions. The lockingmechanism preferably includes biasing means engaging and biasing thelocking elements into the locking position, and the release memberengages the locking elements upon movement thereof to radially drive thelocking elements against the bias into the release position.

Preferably, the release member includes a release sleeve. In oneembodiment, the sleeve includes the inner sleeve portion extendingcoaxially between the interconnected coupling members and having anabutment rim provided by the end region of the inner sleeve portionfacing toward the locking elements. Movement of the release member tooperate the lock release mechanism causes the release sleeve to move inan axial direction toward the locking elements, and engagement with theabutment rim drives the locking elements into the release position, inthis embodiment.

The following description refers to preferred embodiments of thecoupling of the present invention. To facilitate an understanding of theinvention, reference is made in the description to the accompanyingdrawings where the coupling is illustrated in those preferredembodiments. It is to be understood that the coupling is not limited tothe preferred embodiments as hereinafter described and as illustrated inthe drawings.

In the drawings, where like reference numerals identify the same or likecomponents:

FIG. 1 is a longitudinal cross-sectional view of a fluid coupling,according to one preferred embodiment of the present invention, andshowing the male and female coupling members assembled andinterconnected together;

FIG. 2 is a cross-sectional view of the coupling of FIG. 1, takenthrough Section II--II;

FIG. 3 is a longitudinal cross-sectional view similar to FIG. 1, andshowing the coupling members assembled but disconnected ready forseparation; and

FIG. 4 is a longitudinal cross-sectional view of a fluid coupling,according to another preferred embodiment of the present invention, andshowing the male and female coupling members assembled andinterconnected together.

Referring initially to the embodiment of FIGS. 1 to 3, there isgenerally shown a fluid coupling 1 in an assembled, interconnected andoperative condition ready for fluid flow therethrough, although fluidhoses or other lines are not shown connected thereto.

The fluid coupling 1 includes interconnectable male coupling member 2and female coupling member 3. The male and female coupling members 2,3each have tubular coupling bodies 4,5 of single piece construction andgenerally cylindrical in cross-section, although other constructions andcross-sectional shapes may be applicable.

The male coupling body 4 provides an axial fluid flow passage 6extending therealong and having an inlet end 7 and an outlet end 8connectable to a fluid flow line. The female coupling body 5 alsoprovides an axial fluid flow passage 9 extending therealong and havingan inlet end 10 for receiving the inlet end 7 of the male coupling body4 and an outlet end 11 connectable to a separate fluid flow line. Theoutlet ends 8,11 are suitably configured for connection to respectivefluid flow lines for fluid flow therebetween. When assembled, thecoupling members 2,3 are co-axially aligned on a longitudinal axis X.

The male coupling body 4 further includes an outer circumferentialsurface 12, generally configured for sliding mating contact within thefemale coupling member 3, as will be described in more detailhereinafter.

A locking mechanism 13 is provided for selectively, releasablyconnecting coupling members 2,3 together. The locking mechanism 13 iscarried in the female coupling body 5, and includes a plurality oflocking elements 14 which are slidably retained within a circumferentialretaining recess 15 provided in the female coupling body 5. As shownmore clearly in FIG. 2, the retaining recess 15 extends continuouslyabout the internal periphery of the female coupling body 5 and opensradially inwardly into the passage 9.

In this embodiment, the locking elements 14 are in the form of arcuatelocking segments 16 spaced apart along the recess 15 so as to extendabout and project radially into the passage 9.

The locking segments 16 each include a body 17 having ramp or inclinedsurface 18, a front surface 19, an opposite rear surface 20, a retainingsurface 21, an opposite side surface 22, and opposite end surfaces 23.In this embodiment the retaining surface 21 and the side surface 22 ofeach locking segment 16 are adapted for sliding contact with either orboth of the side faces 24,25 respectively, of the recess 15. The extentof contact will vary with the operational condition of the fluidcoupling, ie. whether the coupling members 2,3 are connected ordisconnected, as will become apparent hereinafter.

The locking segments 16 are biased radially out of the recess 15, intothe passage 9. In this locking position, as shown in FIG. 1, the lockingsegments 16 engage with the male coupling member 2 when received inpassage 9. That bias is achieved with any suitable biasing means 26. Inthis embodiment, the biasing means 26 includes a radial biasing spring27, such as a garter spring, extending about the locking segments 16 andseated within a channel 28, formed in the rear surface 20 of eachsegment 16. The biasing spring 27 acts to bias the locking segments 16radially outwardly of the retaining recess 15 into the passage 9. Thatoutward movement of the segments 16 is limited throughsurface-to-surface abutment of juxtaposed end surfaces 23, of adjacentsegments 16, so that the segments 16 are partially retained in therecess 15 at all times.

The male coupling member 2 includes a seating recess 29, extendingcircumferentially about outer surface 12 of the coupling body 4 and intowhich the locking segments 16 are received, in their locking position,under action of the biasing spring 27 when the male coupling member 2 isreceived in the female coupling member 3. The seating recess 29 includesan inclined surface 30, a bottom surface 31 and an abutment surface 32,and is shaped and sized to receive at least a leading portion of thelocking segment 16. It is preferred that the inclined surface 30 be asurface-to-surface engaging fit against the ramp surface 18, and thatthe front surface 19 have a clearance from the bottom surface 31. Thisensures a wedge-like transition fit between the locking segments 16 andthe seating recess 29 such that once engaged, there is little or noaxial movement between the male and female coupling members 2 and 3. Theretaining surface 21 and the abutment surface 32 are also preferred toengage by way of a surface-to-surface engaging fit.

The coupling 1 further includes a lock release mechanism 33 operable toselectively release the locking mechanism 13. The lock release mechanism33 is carried on the female coupling body 5, and includes a lock releasemember 34.

In this embodiment, the release member 34 includes a lock release sleeve35 providing an inner sleeve portion 36 and a flange portion 37extending radially outwardly from one end thereof. The inner sleeveportion 36 is positioned at the inlet end 10 of the female couplingmember 3 and extends into the passage 9 of the female coupling body 5.In addition, the inner sleeve portion 36 extends circumferentially aboutthe male coupling body 4 for sliding and rotational movement over theouter surface 12 thereof. Thus, the inner sleeve portion 36 extendsco-axially between the interconnected coupling members 2,3.

A screw thread connection 38 is provided between the lock release member34 and the female coupling member 3. In particular, the screw threadconnection 38 includes interengageable screw threads 39,40 provided onan outer surface 41 of the inner sleeve portion 36 of the lock releasesleeve 35 and an inner surface 42 in the passage 9 of female couplingbody 5, respectively. It is to be noted, that in the assembled operativecondition of the fluid coupling 1, as shown in FIG. 1, the lock releasemember 34 is in a connecting position, with the threads 39,40 out ofengagement with one another. In this embodiment, multi-start threads39,40 are provided. Four start threads may be used in one embodiment.

In this embodiment, the lock release member 34 also includes anactuating sleeve 43 providing an outer sleeve portion 44 co-axiallysurrounding the female coupling member 3 and connected to the flangeportion 37. The actuating sleeve 43 also provides an inwardly directedflange 45 extending from the outer sleeve portion 44 and engaging aradially outwardly facing groove 46 located on the flange portion 37.The actuating sleeve 43 is slidable longitudinally with respect to thelongitudinal axis X, sliding movement in the direction of arrow A actingto simultaneously move the lock release sleeve 35 in that direction fromthe connecting position.

It should be appreciated, that movement of the lock release sleeve 35can be effected in the absence of the actuating sleeve 43, although thatsleeve 43 serves other functions as will become apparent hereinafter.

Preliminary axial sliding movement of the actuating sleeve 43 in thedirection A moves the lock release member 34 to a preparatory positionwhere the threads 39,40 start engagement with one another. In thisembodiment, that is only a short movement distance and may be of theorder of 0.030" to 0.060". In that position, further movement of thelock release sleeve 35 is restricted to compound axial and rotationalmovement along and about the longitudinal axis X, caused throughprogressive interengagement of the threads 39,40.

Upon continued movement of the lock release member 34 from thepreparatory position to a disconnecting position, an end abutment rim 47of the inner sleeve portion 36 engages against the exposed ramp surface18 of the projecting locking segments 16. The abutment rim 47 applies areleasing force to the locking segments 16 tending to radially move themfrom the seating recess 29, against the bias of the biasing spring 27.That movement moves the locking segments 16 to a release position,thereby removing a retaining influence of the retaining surface 21 onthe abutment surface 32. This disconnecting position is shown in FIG. 3,and in this position the coupling 1 is in an assembled, but disconnectedand in-operative condition.

Having retracted the locking segments 16 from the seating recess 29, totheir release position, the male coupling member 2 is then removablefrom within the female coupling member 3 so as to separate the couplingmembers 2,3.

In this embodiment the actuating sleeve 43 is constructed so as to berotatable about the longitudinal axis X independently of the lockrelease sleeve 35. In this way, the actuating sleeve 43 can at leastsubstantially isolate the lock release sleeve 35 from accidentalrotation leading to engagement of the screw threads 39,40. However, theactuating sleeve 43 and the lock release sleeve 35 may incorporate means(not shown) enabling their driving interconnection for the purpose ofdeliberately rotating the lock release sleeve 35 upon rotation of theactuating sleeve 43 following screw thread engagement. That means mayinclude drive elements, such as ribbing or teeth, on the flange 45 andin the groove 46 which interengage on gripping the actuating sleeve 43and moving the lock release sleeve 35 to the preparatory position.

As an alternative, the actuating sleeve 43 may be formed integrallywith, or permanently secured to, the lock release sleeve 35 such that itcannot rotate independently.

The actuating sleeve 43 extends between the flange portion 37 of thelock release sleeve 35 and an outer surface 48 of the female couplingbody 5 so as to overlie and cover an intervening clearance space 49. Theactuating sleeve 43 can slide and rotate over the outer surface 48taking with it the release sleeve 35.

Movement of the lock release mechanism 33 to force the locking segments16, from the locking position to the release position, disengaging withthe male coupling member 2, enables complete removal of the malecoupling member 2 from engagement within the female coupling member 3.Upon that removal, the lock release sleeve 35 and the actuating sleeve43 can be return moved to the operative condition of the coupling 1 asshown in FIG. 1, ie. the position in which the release member 34 is inthe connecting position with the locking segments 16 projecting from theretaining recess 15 into their locking position. That places the lockingmechanism 13 in a condition ready to automatically engage the malecoupling member 2 at any subsequent time it is inserted within thefemale coupling member 3, to thus retain it in position.

Alternatively, the release member 34 may be left in the disconnectingposition, as shown in FIG. 3, so leaving the locking mechanism 13 in acondition whereby the locking segments 16 remain retracted into theretaining recess 15 in their release position. As a result, the malecoupling member 2 may be subsequently freely inserted into the femalecoupling member 3, without being engaged by the locking mechanism 13. Tothen effect engagement, the lock release member 34 must be return movedfrom its disconnecting position of FIG. 3 to its connecting position ofFIG. 1 in order that the retaining surface 21 partially or fully engagesthe abutment surface 32.

In this embodiment, biasing means 50 act to bias the lock release member34 away from the preparatory position into the connecting position, asshown in FIG. 1. Importantly, that biasing means 50 biases the screwthread 39,40 out of accidental or incidental engagement with oneanother.

The biasing means 50 includes a biasing element 51, such as a coilspring, acting between the release member 34, preferably at a junctionof the sleeve portion 36 and the flange portion 37, and the femalecoupling body 5, preferably adjacent the actuating sleeve 43. In biasingthe release member 34 into the connecting position, the threads 39,40are maintained out of engagement with one another. In this wayaccidental or unintentional release of the male coupling member 2relative to the female coupling member 3, is minimized by resistingaxial movement of the release member 34 toward the preparatory position.In this embodiment, the bias of the spring 50 is overcome by manuallygripping and forcing the actuating sleeve 43 in the direction of arrowA.

In a disassembled operative position of the coupling 1, ie. where thelocking segments 16 are positioned for engagement in the retainingrecess 15 of the male coupling body 4, with the coupling members 2,3,separated, the male coupling body 4 can be axially inserted into thepassage 9. As insertion proceeds, the locking segments 16 ride over aninclined lead-in region 52 on outer surface 12 the male coupling body 4before "snapping" into the seating recess 29. In this assembled,operative condition, as shown in FIG. 1, the lead-in region 52 engagesan adjacent similarly shaped stop region 53 on the female coupling body5. The stop region 53 provides an abutment against which the lead-inregion 52 may abut during insertion of the male coupling member 2 intothe female coupling member 3, such that engagement of these regions52,53 prevents further movement of the male coupling member 2 in thedirection A. This may be useful where the locking segments 16 areretained within the retaining recess 15 by the release member 34 duringinsertion of the male coupling member 2.

As previously indicated, the actuating sleeve 43 also functions to coverover the clearance space 49 containing the biasing element 51 and intowhich the flange portion 37 moves during lock release member 34 movementbetween the connecting and disconnecting positions. As a consequence,the sleeve 43 can prevent dirt, dust and other matter from collecting inthe space 49 or fouling the threads 39,40 and the biasing element 51.The incursion of such matter into the clearance space 49 may adverselyaffect the operation of the fluid coupling 1. In providing that cover,the actuating sleeve 43 remains flush with the female coupling member 3,rather than protruding radially therefrom to cause snagging difficultiesin coupling use.

The actuating sleeve 43 also includes movement limiting means 54 tolimit its movement in a direction opposite to the direction of arrow A.That limiting means 54 includes a limiting member 55 carried by thefemale coupling body 5 and which engages against a lip 56, thuspreventing movement of the lip 56 over the limiting member 55 and offthe female coupling member 3. The female coupling body 5 includesstepped, adjoining recesses 57 and 58 extending about the outer surface48 of the female coupling body 5 and which are configured to separatelyreceive therein the elongate limiting member 55.

The limiting member 55 is preferably of a resiliently flexible naturesuch that during initial assembly of the lock release mechanism 34, thelimiting member 55 may be compressed into the recess 58 to enable theactuating sleeve 43 to be fitted over it. When the actuating sleeve 43has been assembled into a position lying over the recess 58, thelimiting member 55 is relieved of the compressive force and so looselylocated within the recess 57. In this position, the actuating sleeve 43cannot be removed from the female coupling body 5 unless the limitingmember 55 is again compressed into the recess 58.

In this embodiment, the limiting member 55 is in the form of a resilientcirclip.

By providing this movement limiting means 54, the male coupling member 2can be completely removed from the female coupling member 3, withouteither the actuating sleeve 43 or the release sleeve 35 also beingremoved or separated from the female coupling member 3. Thus, therelease member 34 is retained against loss on the female coupling body5.

The coupling 1 also includes means 59 to provide a fluid seal betweenthe interconnected male and female coupling members 2,3. In thisembodiment, the female coupling body 5 includes a seating recess 60extending about the internal periphery of the passage 9 in which anappropriate sealing element (not shown) may be sealingly located forsealing engagement with the outer surface 12 of the male coupling body4. An O-ring or the like sealing element may be provided.

A modified embodiment of the coupling 1 is shown in FIG. 4 of thedrawings. In that embodiment, where the same reference numerals identifythe same or like components as in the previous embodiment, the coupling1 is generally the same as described above.

However, in this embodiment, the female coupling body 5 is constructedin two sections, comprising an outer section 5a and an inner section 5b.This construction facilitates ease of assembly of the fluid coupling 1,particularly with respect to the insertion of the locking segments 16.In that regard the locking segments 16 can be arranged and assembledadjacent the outer section member 5a, prior to connection of thatsection 5a with the inner section 5b in any suitable manner. Ascrew-threaded connection 61 is suitable to interconnect the outer andinner sections 5a,5b.

This modified embodiment also provides inclined retaining and abutmentsurfaces 21,32 on the locking segments 16 and in the seating recess 29,respectively. In addition, the side faces 24,25 of the recess 15 aresimilarly inclined, along with opposite side surfaces 22 of the lockingsegments 16. In this way during release of the locking mechanism 13, thelocking segments 16 are displaced at an angle of inclination equal tothat of the inclined side faces 24,25. The force needed to displace thelocking segments 16 for release may be less in the embodiment of FIG. 3compared with that of FIG. 1, by virtue of that inclination. However,the retaining effect of the locking segments 16 on the male couplingmember 2 is maintained.

Finally, in this embodiment the lock release sleeve 35 and the actuatingsleeve 43 of the release member 34 are formed integral with one another.

A fluid coupling according to the present invention requires adisconnection action which cannot be initiated accidentally orunintentionally. The movement is such that at least one and preferablytwo, separate and distinct movement actions are required fordisconnection. As a result ordinary working conditions are unlikely toeffect accidental disconnection of the fluid coupling. The fluidcoupling thus provides a particularly safe operating environment.

Those skilled in the art will appreciate that there may be manyvariations and modifications of the coupling described herein which arewithin the scope of the present invention as defined in the claimsappended hereto.

I claim:
 1. A female coupling member, releasably interconnectable with amale coupling member to form a fluid coupling, the female couplingmember comprising:a tubular body having an inlet end for axiallyreceiving the inlet end of the male coupling member, and an outlet endconnectable to a fluid flow line; a locking mechanism operable to exerta retaining influence on the male coupling member, when received withinthe female coupling member, to releasably interconnect the male andfemale coupling members; and, a lock release mechanism selectivelyoperable to remove the retaining influence of the locking mechanism soas to release the male and female coupling members, the lock releasemechanism including:release member being manually movable to operate thelock release mechanism, movement of the release member including apreliminary movement to a preparatory position in which the lock releasemember is then able to operate the lock release mechanism to remove theretaining influence thereof followed by a further movement in at least anon-axial direction which operates the lock release mechanism to removethe retaining influence; and, biasing means acting on the release memberto bias the release member away from the preparatory position, therelease member being manually moved to the preparatory position againstthe bias of the biasing means.
 2. A female coupling member as claimed inclaim 1, wherein the preliminary movement of the release member is in adirection along a longitudinal axis of the coupling, and the furthermovement of the release member is in a direction about the longitudinalaxis of the coupling.
 3. A female coupling member as claimed in claim 1,wherein the lock release mechanism is slidably carried on the tubularcoupling body, and the release member slidably moves along the tubularcoupling body during the preliminary movement.
 4. A female couplingmember as claimed in claim 1, wherein the release member moves duringthe further movement in compound rotational and lineal directionsrespectively about and along a longitudinal axis of the coupling inorder to operate the lock release mechanism.
 5. A female coupling memberas claimed in claim 4, wherein the lock release mechanism is carried onthe tubular coupling body, and includes at least one screw thread on thecoupling body and at least one co-operable screw thread on the releasemember, the screw threads progressively interengaging upon rotation ofthe release member to cause the release member to move in the compoundrotational and lineal directions.
 6. A female coupling member as claimedin claim 5, wherein the coupling body defines an axial fluid flowpassage and the screw thread on the coupling body is provided on aninner surface in the flow passage, and the release member includes aninner sleeve portion extending into the flow passage, the screw threadof the release member being provided on an outer surface of the innersleeve portion.
 7. A female coupling member as claimed in claim 6,wherein the screw threads are disengageable upon reverse directionrotation of the release member, and upon disengagement the screw threadsare axially spaced apart, the release member being axially movablerelative to the coupling body member during the preliminary movement inorder to bring the screw threads into engagement.
 8. A female couplingmember as claimed in claim 7, wherein the biasing means includes abiasing element acting on the release member to bias the release memberin an axial direction in which the disengaged screw threads aremaintained in spaced apart relation, the release member being manuallymovable against the bias to bring the screw threads into engagement. 9.A female coupling member as claimed in claim 8, wherein the biasingelement is a biasing spring mounted in a circumferential clearance spaceformed between the release member and the coupling body at the inlet endthereof, and acts between the release member and coupling body.
 10. Afemale coupling member as claimed in claim 5, wherein multi-start screwthreads are provided on the coupling body member and the release member.11. A female coupling member as claimed in claim 6 wherein the releasemember includes an outer sleeve portion coaxially surrounding thecoupling body and connected to the inner sleeve portion, the outersleeve portion being manually grippable for movement to progressivelyinterengage the screw threads.
 12. A female coupling member as claimedin claim 11, wherein the release member includes a flange portionextending radially from the inner sleeve portion, and the outer sleeveportion is connected to the flange portion in order to move the innersleeve portion for engagement of the screw threads.
 13. A femalecoupling member as claimed in claim 12, wherein the outer sleeve portionand flange portion are formed integral with one another.
 14. A femalecoupling member as claimed in claim 12, wherein the flange portion has acircumferentially extending and radially outwardly facing groove, andthe outer sleeve portion has a circumferentially extending and inwardlyfacing flange engaging in the groove to connect the outer sleeve portionto the flange portion.
 15. A female coupling member as claimed in claim8, wherein the release member includes an outer sleeve portionco-axially surrounding the coupling body and connected to the innersleeve portion, the outer sleeve portion overlying and covering theclearance space and biasing spring between the release member and thetubular coupling body, and the outer sleeve portion being manuallygrippable for movement to progressively interengage the screw threads.16. A female coupling member as claimed in claim 1, wherein the lockingmechanism includes a plurality of locking elements movable between arelease position disengaging from the male coupling member and a lockingposition in which the locking members extend between the couplingmembers and engage the male coupling member thereby to releasablyinterconnect the coupling members together, the release member uponmovement to operate the lock release mechanism engaging the lockingelements and moving them to their release position to disengage thecoupling members.
 17. A female coupling member as claimed in claim 16,wherein the locking mechanism includes a circumferential retainingrecess provided in the coupling body, and the locking elements includearcuate locking segments positioned in side-by-side relation along therecess for inward movement from the release position to the lockingposition.
 18. A female coupling member as claimed in claim 17, whereinthe locking elements are generally radially movable between the releaseand locking positions, the locking mechanism includes biasing meansengaging and biasing the locking elements into the locking position, andthe release member engages the locking elements upon movement thereof toradially drive the locking elements against the bias into the releaseposition.
 19. A female coupling member as claimed in claim 18, whereinthe release member includes a release sleeve extending coaxially betweenthe interconnected coupling members and having an abutment rim facingtoward the locking elements, whereupon movement of the release member tooperate the lock release mechanism causes the release sleeve to move inan axial direction toward the locking elements, engagement with theabutment rim driving the locking elements into the release position. 20.A female coupling member as claimed in claim 19, wherein each of thelocking elements has an inclined surface with which the abutment rimengages to radially drive the locking elements.
 21. A female couplingmember as claimed in claim 19, wherein the release sleeve includes theinner sleeve portion, and the abutment rim is provided by an end regionof the inner sleeve portion.
 22. A fluid coupling for interconnectingfluid flow lines, including:a tubular male coupling member having aninlet end, and an outlet end connectable to a fluid flow line; a tubularfemale coupling member having an inlet end for axially receiving theinlet end of the male coupling member, and an outlet end connectable toa fluid flow line; a locking mechanism operable to exert a retaininginfluence on the male coupling member, when received within the femalecoupling member, to releasably interconnect the male and female couplingmembers, and, a lock release mechanism selectively operable to removethe retaining influence of the locking mechanism so as to release themale and female coupling members, the lock release mechanism includingarelease member being manually movable at least in a non-axial directionto operate the lock release mechanism, movement of the release memberincluding a preliminary movement to a preparatory position in which thelock release member is then able to operate the lock release mechanismto remove the retaining influence thereof followed by a further movementin at least a non-axial direction which operates the lock releasemechanism to remove the retaining influence; and, biasing means actingon the release member to bias the release member away from thepreparatory position, the release member being manually moved to thepreparatory position against the bias of the biasing means.
 23. A femalecoupling member as claimed in claim 22, wherein the preliminary movementof the release member is in a direction along a longitudinal axis of thecoupling, and the further movement of the release member is in adirection about the longitudinal axis of the coupling.
 24. A femalecoupling member as claimed in claim 23, wherein the lock releasemechanism is slidably carried on the tubular coupling body, and therelease member slidably moves along the tubular coupling body during thepreliminary movement.
 25. A female coupling member as claimed in claim24, wherein the release member moves during the further movement incompound rotational and lineal directions respectively about and along alongitudinal axis of the coupling in order to operate the lock releasemechanism.
 26. A fluid coupling as claimed in claim 25, wherein the lockrelease mechanism is carried on the female coupling member, and includesat least one screw thread on the female coupling member and at least oneco-operable screw thread on the release member, the screw threadsprogressively interengaging upon rotation of the release member to causethe release member to move in the compound rotational and linealdirections.
 27. A fluid coupling as claimed in claim 26, wherein thefemale coupling member includes a tubular coupling body defining anaxial fluid flow passage, the screw thread of the female coupling memberbeing provided on an inner surface in the flow passage of the couplingbody, and the release member includes an inner sleeve portion extendinginto the flow passage, the screw thread of the release member beingprovided on an outer surface of the inner sleeve portion.
 28. A fluidcoupling as claimed in claim 27, wherein the screw threads aredisengageable upon reverse direction rotation of the release member, andupon disengagement the screw threads are axially spaced apart, therelease member being axially movable relative to the female couplingmember during the preliminary movement in order to bring the screwthreads into engagement.
 29. A fluid coupling as claimed in claim 28,wherein the biasing means includes a biasing element acting on therelease member to bias the release member in an axial direction in whichthe disengaged screw threads are maintained in spaced apart relation,the release member being manually movable against the bias to bring thescrew threads into engagement.
 30. A fluid coupling as claimed in claim29, wherein the biasing element is a biasing spring mounted in acircumferential clearance space formed between the release member andthe tubular coupling body at the inlet end of the female couplingmember, and acts between the release member and tubular coupling body.31. A fluid coupling as claimed in claim 30, wherein the release memberincludes an outer sleeve portion coaxially surrounding the tubularcoupling body and connected to the inner sleeve portion, the outersleeve portion being manually grippable for movement to progressivelyinterengage the screw threads.
 32. A fluid coupling as claimed in claim31, wherein the outer sleeve portion overlies and covers the clearancespace and biasing spring between the release member and the tubularcoupling body.
 33. A fluid coupling as claimed in claim 22, wherein thelocking mechanism includes a plurality of locking elements carried byone of the coupling members and movable between a release positiondisengaging from the other coupling member and a locking position inwhich the locking members extend between the coupling members and engagethe other coupling member thereby to releasably interconnect thecoupling members together, the release member upon movement to operatethe lock release mechanism engaging the locking elements and moving themto their release position to disengage the coupling members.
 34. A fluidcoupling as claimed in claim 33, wherein the locking mechanism includesa circumferential retaining recess provided in the female couplingmember, and the locking elements include arcuate locking segmentspositioned in side-by-side relation along the recess for inward movementfrom the release position to the locking position.
 35. A fluid couplingas claimed in claim 34, wherein the locking elements are generallyradially movable between the release and locking positions, the lockingmechanism includes biasing means engaging and biasing the lockingelements into the locking position, and the release member engages thelocking elements upon movement thereof to radially drive the lockingelements against the bias into the release position.
 36. A fluidcoupling as claimed in claim 35, wherein the release member includes arelease sleeve extending coaxially between the interconnected couplingmembers and having an abutment rim facing toward the locking elements,whereupon movement of the release member to operate the lock releasemechanism causes the release sleeve to move in an axial direction towardthe locking elements, engagement with the abutment rim driving thelocking elements into the release position.
 37. A female couplingmember, releasably interconnectable with a male coupling member to forma fluid coupling, the female coupling member comprising:a tubularcoupling body having an inlet end for axially receiving the inlet end ofthe male coupling member, and an outlet end connectable to a fluid flowline; a locking mechanism operable to exert a retaining influence on themale coupling member, when received within the female coupling member,to releasably interconnect the male and female coupling members; and, alock release mechanism selectively operable to remove the retaininginfluence of the locking mechanism so as to release the male and femalecoupling members, the lock release mechanism including:a release memberbeing manually movable to operate the lock release mechanism movement ofthe release member including a preliminary movement to a preparatoryposition in which the lock release member is then able to operate thelock release mechanism to remove the retaining influence thereoffollowed by a further movement which operates the lock release mechanismto remove the retaining influence, the preliminary movement of therelease member being in a direction along a longitudinal axis of thecoupling, and the further movement of the release member being incompound rotational and lineal directions respectively about and alongthe longitudinal axis of the coupling,wherein the lock release member isslidably and rotatably carried on the tubular coupling body, andslidably moves along the tubular coupling body during the preliminarymovement, and the lock release mechanism includes at least one screwthread on the coupling body and at least one co-operable screw thread onthe release member, the screw threads progressively interengaging uponrotation of the release member on the tubular coupling body to cause therelease member to move in the compound rotational and linealdirections,wherein the screw threads are disengageable upon reversedirection rotation of the release member, and upon disengagement thescrew threads are axially spaced apart, the release member being axiallymovable relative to the coupling body member during the preliminarymovement in order to bring the screw threads into engagement, andwherein the lock release mechanism includes a biasing element acting onthe release member to bias the release member in an axial direction inwhich the disengaged screw threads are maintained in spaced apartrelation, the release member being manually movable against the biasingelement to bring the screw threads into engagement.